Pulmonary edema, also known as pulmonary congestion, is excessive
liquid accumulation in the
tissue and
air spaces (usually
alveoli Alveolus (; pl. alveoli, adj. alveolar) is a general anatomical term for a concave cavity or pit.
Uses in anatomy and zoology
* Pulmonary alveolus, an air sac in the lungs
** Alveolar cell or pneumocyte
** Alveolar duct
** Alveolar macrophage
* M ...
) of the
lung
The lungs are the primary organs of the respiratory system in humans and most other animals, including some snails and a small number of fish. In mammals and most other vertebrates, two lungs are located near the backbone on either side of ...
s.
It leads to impaired
gas exchange
Gas exchange is the physical process by which gases move passively by diffusion across a surface. For example, this surface might be the air/water interface of a water body, the surface of a gas bubble in a liquid, a gas-permeable membrane, or a ...
and may cause
hypoxemia
Hypoxemia is an abnormally low level of oxygen in the blood. More specifically, it is oxygen deficiency in arterial blood. Hypoxemia has many causes, and often causes hypoxia as the blood is not supplying enough oxygen to the tissues of the bod ...
and
respiratory failure
Respiratory failure results from inadequate gas exchange by the respiratory system, meaning that the arterial oxygen, carbon dioxide, or both cannot be kept at normal levels. A drop in the oxygen carried in the blood is known as hypoxemia; a rise ...
. It is due to either failure of the
left ventricle
A ventricle is one of two large chambers toward the bottom of the heart that collect and expel blood towards the peripheral beds within the body and lungs. The blood pumped by a ventricle is supplied by an atrium, an adjacent chamber in the uppe ...
of the
heart
The heart is a muscular Organ (biology), organ in most animals. This organ pumps blood through the blood vessels of the circulatory system. The pumped blood carries oxygen and nutrients to the body, while carrying metabolic waste such as ca ...
to remove oxygenated blood adequately from the
pulmonary circulation
The pulmonary circulation is a division of the circulatory system in all vertebrates. The circuit begins with deoxygenated blood returned from the body to the right atrium of the heart where it is pumped out from the right ventricle to the lungs ...
(cardiogenic pulmonary edema), or an injury to the
lung tissue directly or
blood vessel
The blood vessels are the components of the circulatory system that transport blood throughout the human body. These vessels transport blood cells, nutrients, and oxygen to the tissues of the body. They also take waste and carbon dioxide awa ...
s of the lung (non-cardiogenic pulmonary edema).
Treatment is focused on three aspects: firstly improving respiratory function, secondly, treating the underlying cause, and thirdly preventing further damage and assuring full recovery to the lung. Pulmonary edema, especially when sudden (acute), can lead to
respiratory failure
Respiratory failure results from inadequate gas exchange by the respiratory system, meaning that the arterial oxygen, carbon dioxide, or both cannot be kept at normal levels. A drop in the oxygen carried in the blood is known as hypoxemia; a rise ...
or
cardiac arrest
Cardiac arrest is when the heart suddenly and unexpectedly stops beating. It is a medical emergency that, without immediate medical intervention, will result in sudden cardiac death within minutes. Cardiopulmonary resuscitation (CPR) and possi ...
due to
hypoxia. It is a cardinal feature of
congestive heart failure
Heart failure (HF), also known as congestive heart failure (CHF), is a syndrome, a group of signs and symptoms caused by an impairment of the heart's blood pumping function. Symptoms typically include shortness of breath, excessive fatigue, ...
. The term edema is from the
Greek
Greek may refer to:
Greece
Anything of, from, or related to Greece, a country in Southern Europe:
*Greeks, an ethnic group.
*Greek language, a branch of the Indo-European language family.
**Proto-Greek language, the assumed last common ancestor ...
(''oidēma'', "swelling"), from οἰδέω (''oidéō'', "(I) swell").
Types
Classically it is cardiogenic (left
ventricular) but fluid may also accumulate due to damage to the lung. This damage may be from direct external injuries or injuries mediated by high pressures within the pulmonary circulation. When directly or indirectly caused by increased left ventricular pressure, pulmonary edema may form when mean pulmonary pressure rises from the normal average of 15 mmHg to above 25 mmHg, where pulmonary fluid may form. Broadly, the causes of pulmonary edema can be divided into cardiogenic and non-cardiogenic. By convention, cardiogenic specifically refers to left ventricular causes.
Cardiogenic
* Congestive heart failure which is due to the heart's inability to pump the blood out of the pulmonary circulation at a sufficient rate resulting in elevation in
pulmonary wedge pressure
The pulmonary wedge pressure (PWP), also called pulmonary arterial wedge pressure (PAWP), pulmonary capillary wedge pressure (PCWP), pulmonary artery occlusion pressure (PAOP), or cross-sectional pressure, is the pressure measured by wedging a pulm ...
and edema – this usually is due to left ventricular failure, but may also be from arrhythmias, or fluid overload, (e.g. from
kidney failure
Kidney failure, also known as end-stage kidney disease, is a medical condition in which the kidneys can no longer adequately filter waste products from the blood, functioning at less than 15% of normal levels. Kidney failure is classified as eit ...
or
intravenous therapy
Intravenous therapy (abbreviated as IV therapy) is a medical technique that administers fluids, medications and nutrients directly into a person's vein. The intravenous route of administration is commonly used for rehydration or to provide nutri ...
).
*
Hypertensive crisis
Severely elevated blood pressure (equal to or greater than a systolic 180 or diastolic of 120—sometimes termed malignant or accelerated hypertension) is referred to as a hypertensive crisis, as blood pressure at this level confers a high risk ...
can cause pulmonary edema as the elevation in blood pressure and increased
afterload
Afterload is the pressure that the heart must work against to eject blood during systole (ventricular contraction). Afterload is proportional to the average arterial pressure. As aortic and pulmonary pressures increase, the afterload increases on ...
on the left ventricle hinders forward flow in blood vessels and causes the elevation in
wedge pressure
The pulmonary wedge pressure (PWP), also called pulmonary arterial wedge pressure (PAWP), pulmonary capillary wedge pressure (PCWP), pulmonary artery occlusion pressure (PAOP), or cross-sectional pressure, is the pressure measured by wedging a pulm ...
and subsequent pulmonary edema.
Non-cardiogenic
*
Negative pressure pulmonary edema Negative-pressure pulmonary edema (NPPE), also known as Postobstructive Pulmonary Edema, is a clinical phenomenon that results from the generation of large negative pressures in the airways during attempted inspiration against some form of obstructi ...
in which a significant negative (internal) pressure in the chest (such as from an inhalation against an upper airway obstruction) ruptures capillaries and floods the alveoli with blood. Negative pressure pulmonary edema has an incidence in the range of 0.05-0.1% in cases of general anesthesia. The negative pressure causes a significant increase in preload, thereby increasing pulmonary blood volume. There is also a significant increase in left ventricular afterload, which causes a decreased cardiac output. The increase in pulmonary blood volume and pressure along with a decrease in cardiac output to the lungs will increase the pulmonary transudative pressures and the risk of pulmonary edema. With all this occurring, pulmonary vascular resistance increases causing a shift of the intraventricular septum. The ventricular septal shift to the left causes a left ventricular diastolic dysfunction, which further increases pulmonary hydrostatic pressures and the risk.
* Neurogenic causes (
seizures
An epileptic seizure, informally known as a seizure, is a period of symptoms due to abnormally excessive or synchronous neuronal activity in the brain. Outward effects vary from uncontrolled shaking movements involving much of the body with lo ...
, head trauma,
strangulation
Strangling is compression of the neck that may lead to unconsciousness or death by causing an increasingly hypoxic state in the brain. Fatal strangling typically occurs in cases of violence, accidents, and is one of two main ways that hangin ...
,
electrocution
Electrocution is death or severe injury caused by electric shock from electric current passing through the body. The word is derived from "electro" and "execution", but it is also used for accidental death.
The term "electrocution" was coin ...
).
*
Pulmonary embolism
Pulmonary embolism (PE) is a blockage of an artery in the lungs by a substance that has moved from elsewhere in the body through the bloodstream ( embolism). Symptoms of a PE may include shortness of breath, chest pain particularly upon breathin ...
Acute lung injury
Acute respiratory distress syndrome (ARDS) is a type of respiratory failure characterized by rapid onset of widespread inflammation in the lungs. Symptoms include shortness of breath (dyspnea), rapid breathing (tachypnea), and bluish skin colo ...
may also cause pulmonary edema directly through injury to the vasculature and parenchyma of the lung. It includes acute lung injury and
acute respiratory distress syndrome
Acute respiratory distress syndrome (ARDS) is a type of respiratory failure characterized by rapid onset of widespread inflammation in the lungs. Symptoms include shortness of breath (dyspnea), rapid breathing (tachypnea), and bluish skin colo ...
. (ALI-ARDS) cover many of these causes, but they may also include:
* Inhalation of hot or toxic gases
*
Pulmonary contusion
A pulmonary contusion, also known as lung contusion, is a bruise of the lung, caused by chest trauma. As a result of damage to capillaries, blood and other fluids accumulate in the lung tissue. The excess fluid interferes with gas exchange, pot ...
, i.e.,
high-energy trauma (e.g. vehicle accidents)
*
Aspiration, e.g., gastric fluid
* Reexpansion, i.e. post large volume
thoracocentesis, resolution of pneumothorax, post decortication, removal of endobronchial obstruction, effectively a form of negative pressure pulmonary oedema.
* Reperfusion injury, i.e., postpulmonary
thromboendartectomy or
lung transplantation
Lung transplantation, or pulmonary transplantation, is a surgical procedure in which one or both lungs are replaced by lungs from a donor. Donor lungs can be retrieved from a living or deceased donor. A living donor can only donate one lung lobe. ...
*
Swimming induced pulmonary edema also known as immersion pulmonary edema
* Transfusion Associated Circulatory Overload occurs when multiple
blood transfusion
Blood transfusion is the process of transferring blood products into a person's circulation intravenously. Transfusions are used for various medical conditions to replace lost components of the blood. Early transfusions used whole blood, but mo ...
s or blood-products (plasma, platelets, etc.) are transfused over a short period of time.
* Transfusion associated Acute Lung Injury is a specific type of blood-product transfusion injury that occurs when the donors plasma contained antibodies against the recipient, such as anti-HLA or anti-neutrophil antibodies.
* Severe
infection
An infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable di ...
or
inflammation
Inflammation (from la, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants, and is a protective response involving immune cells, blood vessels, and molec ...
which may be local or systemic. This is the classical form of
acute lung injury
Acute respiratory distress syndrome (ARDS) is a type of respiratory failure characterized by rapid onset of widespread inflammation in the lungs. Symptoms include shortness of breath (dyspnea), rapid breathing (tachypnea), and bluish skin colo ...
-
adult respiratory distress syndrome
Acute respiratory distress syndrome (ARDS) is a type of respiratory failure characterized by rapid onset of widespread inflammation in the lungs. Symptoms include shortness of breath (dyspnea), rapid breathing (tachypnea), and bluish skin c ...
.
Some causes of pulmonary edema are less well characterised and arguably represent specific instances of the broader classifications above.
*
Arteriovenous malformation
Arteriovenous malformation is an abnormal connection between arteries and veins, bypassing the capillary system. This vascular anomaly is widely known because of its occurrence in the central nervous system (usually cerebral AVM), but can app ...
*
Hantavirus
''Orthohantavirus'' is a genus of single-stranded, enveloped, negative-sense RNA viruses in the family '' Hantaviridae'' within the order ''Bunyavirales''. Members of this genus may be called orthohantaviruses or simply hantaviruses.
Orthohantav ...
pulmonary syndrome
*
High altitude pulmonary edema (HAPE)
*
Envenomation
Envenomation is the process by which venom is injected by the bite or sting of a venomous animal.
Many kinds of animals, including mammals (e.g., the northern short-tailed shrew, ''Blarina brevicauda''), reptiles (e.g., the king cobra), spiders ...
, such as with the venom of
Atrax robustus
Signs and symptoms
The most common symptom of pulmonary edema is
difficulty breathing (dyspnea), but may include other symptoms such as
coughing up blood (classically seen as pink or red, frothy sputum),
excessive sweating
Hyperhidrosis is a condition characterized by abnormally increased sweating, in excess of that required for regulation of body temperature. Although primarily a benign physical burden, hyperhidrosis can deteriorate quality of life from a psychologi ...
,
anxiety
Anxiety is an emotion which is characterized by an unpleasant state of inner turmoil and includes feelings of dread over anticipated events. Anxiety is different than fear in that the former is defined as the anticipation of a future threat wh ...
, and
pale skin
Pallor is a pale color of the skin that can be caused by illness, emotional shock or stress, stimulant use, or anemia, and is the result of a reduced amount of oxyhaemoglobin and may also be visible as pallor of the conjunctivae of the eyes o ...
.
Shortness of breath
Shortness of breath (SOB), also medically known as dyspnea (in AmE) or dyspnoea (in BrE), is an uncomfortable feeling of not being able to breathe well enough. The American Thoracic Society defines it as "a subjective experience of breathing di ...
can manifest as
orthopnea
Orthopnea or orthopnoea is shortness of breath (dyspnea) that occurs when lying flat, causing the person to have to sleep propped up in bed or sitting in a chair. It is commonly seen as a late manifestation of heart failure, resulting from fluid ...
(inability to breath sufficiently when lying down flat due to breathlessness) and/or
paroxysmal nocturnal dyspnea
Paroxysmal nocturnal dyspnea or paroxysmal nocturnal dyspnoea (PND) is an attack of severe shortness of breath and coughing that generally occurs at night. It usually awakens the person from sleep, and may be quite frightening. PND, as well as simp ...
(episodes of severe sudden breathlessness at night). These are common presenting symptoms of chronic and cardiogenic pulmonary edema due to left ventricular failure. The development of pulmonary edema may be associated with symptoms and signs of "fluid overload" in the lungs; this is a non-specific term to describe the manifestations of ''right'' ventricular failure on the rest of the body and includes peripheral
edema
Edema, also spelled oedema, and also known as fluid retention, dropsy, hydropsy and swelling, is the build-up of fluid in the body's tissue. Most commonly, the legs or arms are affected. Symptoms may include skin which feels tight, the area ma ...
(swelling of the legs, in general, of the "pitting" variety, wherein the skin is slow to return to normal when pressed upon due to fluid), raised
jugular venous pressure
The jugular venous pressure (JVP, sometimes referred to as ''jugular venous pulse'') is the indirectly observed pressure over the venous system via visualization of the internal jugular vein. It can be useful in the differentiation of different fo ...
and
hepatomegaly
Hepatomegaly is the condition of having an enlarged liver. It is a non-specific medical sign having many causes, which can broadly be broken down into infection, hepatic tumours, or metabolic disorder. Often, hepatomegaly will present as an abdo ...
, where the liver is excessively enlarged and may be tender or even pulsatile. Other signs include end-inspiratory
crackles
Crackles are the clicking, rattling, or crackling noises that may be made by one or both lungs of a human with a respiratory disease during inhalation. They are usually heard only with a stethoscope ("on auscultation"). Pulmonary crackles are a ...
(crackling sounds heard at the end of a deep breath) on
auscultation
Auscultation (based on the Latin verb ''auscultare'' "to listen") is listening to the internal sounds of the body, usually using a stethoscope. Auscultation is performed for the purposes of examining the circulatory and respiratory systems (he ...
and the presence of a
third heart sound
The third heart sound or S3 is a rare extra heart sound that occurs soon after the normal two "lub-dub" heart sounds (S1 and S2). S3 is associated with heart failure.
Physiology
It occurs at the beginning of the middle third of diastole, approxima ...
.
[
]
Flash pulmonary edema
''Flash pulmonary edema'' (''FPE''), is rapid onset acute pulmonary edema. It is most often precipitated by acute myocardial infarction
A myocardial infarction (MI), commonly known as a heart attack, occurs when blood flow decreases or stops to the coronary artery of the heart, causing damage to the heart muscle. The most common symptom is chest pain or discomfort which may t ...
or mitral regurgitation
Mitral regurgitation (MR), also known as mitral insufficiency or mitral incompetence, is a form of valvular heart disease in which the mitral valve is insufficient and does not close properly when the heart pumps out blood. Section: Valvular H ...
, but can be also caused by aortic regurgitation
Aortic regurgitation (AR), also known as aortic insufficiency (AI), is the leaking of the aortic valve of the heart that causes blood to flow in the reverse direction during ventricular diastole, from the aorta into the left ventricle. As a cons ...
, heart failure
Heart failure (HF), also known as congestive heart failure (CHF), is a syndrome, a group of signs and symptoms caused by an impairment of the heart's blood pumping function. Symptoms typically include shortness of breath, excessive fatigue, ...
, or almost any cause leading to elevated left ventricular filling pressures. Treatment of FPE should be directed at the underlying cause, but the mainstays are nitroglycerin, ensuring adequate oxygenation with non-invasive ventilation, and decrease of pulmonary circulation pressures while FPE stays.
Recurrence of FPE is thought to be associated with hypertension
Hypertension (HTN or HT), also known as high blood pressure (HBP), is a long-term medical condition in which the blood pressure in the arteries is persistently elevated. High blood pressure usually does not cause symptoms. Long-term high b ...
and may signify renal artery stenosis
Renal artery stenosis (RAS) is the narrowing of one or both of the renal arteries, most often caused by atherosclerosis or fibromuscular dysplasia. This narrowing of the renal artery can impede blood flow to the target kidney, resulting in renov ...
. Prevention of recurrence is based on managing or preventing hypertension, coronary artery disease
Coronary artery disease (CAD), also called coronary heart disease (CHD), ischemic heart disease (IHD), myocardial ischemia, or simply heart disease, involves the reduction of blood flow to the heart muscle due to build-up of atherosclerotic pl ...
, renovascular hypertension
Renovascular hypertension is a condition in which high blood pressure is caused by the kidneys' hormonal response to narrowing of the arteries supplying the kidneys. When functioning properly this hormonal axis regulates blood pressure. Due to l ...
, and heart failure.
Diagnosis
There is no single test for confirming that breathlessness is caused by pulmonary edema – there are many causes of shortness of breath
Shortness of breath (SOB), also medically known as dyspnea (in AmE) or dyspnoea (in BrE), is an uncomfortable feeling of not being able to breathe well enough. The American Thoracic Society defines it as "a subjective experience of breathing di ...
; but there are methods to suggest a high probability of an edema.
Low oxygen saturation
Oxygen saturation (symbol SO2) is a relative measure of the concentration of oxygen that is dissolved or carried in a given medium as a proportion of the maximal concentration that can be dissolved in that medium at the given temperature. It ca ...
in blood and disturbed arterial blood gas
An arterial blood gas (ABG) test, or arterial blood gas analysis (ABGA) measures the amounts of arterial gases, such as oxygen and carbon dioxide. An ABG test requires that a small volume of blood be drawn from the radial artery with a syringe an ...
readings support the proposed diagnosis by suggesting a pulmonary shunt
A pulmonary shunt is the passage of deoxygenated blood from the right side of the heart to the left without participation in gas exchange in the pulmonary capillaries. It is a pathological condition that results when the alveoli of parts of the lun ...
. A chest X-ray
A chest radiograph, called a chest X-ray (CXR), or chest film, is a projection radiograph of the chest used to diagnose conditions affecting the chest, its contents, and nearby structures. Chest radiographs are the most common film taken in me ...
will show fluid in the alveolar walls, Kerley B lines, increased vascular shadowing in a classical batwing peri- hilum pattern, upper lobe diversion (biased blood flow to the superior parts instead of inferior parts of the lung), and possibly pleural effusion
A pleural effusion is accumulation of excessive fluid in the pleural space, the potential space that surrounds each lung.
Under normal conditions, pleural fluid is secreted by the parietal pleural capillaries at a rate of 0.6 millilitre per k ...
s. In contrast, patchy alveolar infiltrates are more typically associated with noncardiogenic edema[
Lung ]ultrasound
Ultrasound is sound waves with frequencies higher than the upper audible limit of human hearing. Ultrasound is not different from "normal" (audible) sound in its physical properties, except that humans cannot hear it. This limit varies ...
s, employed by a healthcare provider at the point of care, is also a useful tool to diagnose pulmonary edema; not only is it accurate, but it may quantify the degree of lung water, track changes over time, and differentiate between cardiogenic and non-cardiogenic edema.
Especially in the case of cardiogenic pulmonary edema, urgent echocardiography
An echocardiography, echocardiogram, cardiac echo or simply an echo, is an ultrasound of the heart.
It is a type of medical imaging of the heart, using standard ultrasound or Doppler ultrasound.
Echocardiography has become routinely used in ...
may strengthen the diagnosis by demonstrating impaired left ventricular function, high central venous pressure Central venous pressure (CVP) is the blood pressure in the venae cavae, near the right atrium of the heart. CVP reflects the amount of blood returning to the heart and the ability of the heart to pump the blood back into the arterial system. CVP ...
s and high pulmonary artery
A pulmonary artery is an artery in the pulmonary circulation that carries deoxygenated blood from the right side of the heart to the lungs. The largest pulmonary artery is the ''main pulmonary artery'' or ''pulmonary trunk'' from the heart, and ...
pressures leading to pulmonary edema.
Blood tests are performed for electrolyte
An electrolyte is a medium containing ions that is electrically conducting through the movement of those ions, but not conducting electrons. This includes most soluble salts, acids, and bases dissolved in a polar solvent, such as water. Upon ...
s (sodium, potassium) and markers of renal function
Assessment of kidney function occurs in different ways, using the presence of symptoms and signs, as well as measurements using urine tests, blood tests, and medical imaging.
Functions of a healthy kidney include maintaining a person's flui ...
(creatinine, urea). Liver enzyme
Liver function tests (LFTs or LFs), also referred to as a hepatic panel, are groups of blood tests that provide information about the state of a patient's liver. These tests include prothrombin time (PT/INR), activated partial thromboplastin tim ...
s, inflammatory markers (usually C-reactive protein
C-reactive protein (CRP) is an annular (ring-shaped) pentameric protein found in blood plasma, whose circulating concentrations rise in response to inflammation. It is an acute-phase protein of hepatic origin that increases following interleukin- ...
) and a complete blood count
A complete blood count (CBC), also known as a full blood count (FBC), is a set of medical laboratory tests that provide information about the cells in a person's blood. The CBC indicates the counts of white blood cells, red blood cells and ...
as well as coagulation
Coagulation, also known as clotting, is the process by which blood changes from a liquid to a gel, forming a blood clot. It potentially results in hemostasis, the cessation of blood loss from a damaged vessel, followed by repair. The mechanism ...
studies (PT, aPTT) are also typically requested as further diagnosis. B-type natriuretic peptide (BNP) is available in many hospitals, sometimes even as a point-of-care test. Low levels of BNP (<100 pg/ml) suggest a cardiac cause is unlikely.[
]
Prevention
In those with underlying heart or lung disease, effective control of congestive and respiratory symptoms helps prevents pulmonary edema.
Dexamethasone
Dexamethasone is a glucocorticoid medication used to treat rheumatic problems, a number of skin diseases, severe allergies, asthma, chronic obstructive lung disease, croup, brain swelling, eye pain following eye surgery, superior vena ...
is in widespread use for the prevention of high altitude pulmonary edema
High-altitude pulmonary edema (HAPE) is a life-threatening form of non-cardiogenic pulmonary edema that occurs in otherwise healthy people at altitudes typically above . However, cases have also been reported between in more vulnerable subjects.
...
. Sildenafil
Sildenafil, sold under the brand name Viagra, among others, is a medication used to treat erectile dysfunction and pulmonary arterial hypertension. It is unclear if it is effective for treating sexual dysfunction in women. It is taken by ...
is used as a preventive treatment for altitude-induced pulmonary edema and pulmonary hypertension, the mechanism of action is via phosphodiesterase inhibition which raises cGMP, resulting in pulmonary arterial vasodilation and inhibition of smooth muscle cell proliferation and indirectly fluid formation in the lungs. While this effect has only recently been discovered, sildenafil is already becoming an accepted treatment for this condition, in particular in situations where the standard treatment of rapid descent (acclimatization) has been delayed for some reason.
Management
The initial management of pulmonary edema, irrespective of the type or cause, is supporting vital functions while edema lasts. Therefore, if the level of consciousness is decreased it may be required to proceed to tracheal intubation
Tracheal intubation, usually simply referred to as intubation, is the placement of a flexible plastic tube into the trachea (windpipe) to maintain an open airway or to serve as a conduit through which to administer certain drugs. It is frequentl ...
and mechanical ventilation
Mechanical ventilation, assisted ventilation or intermittent mandatory ventilation (IMV), is the medical term for using a machine called a ventilator to fully or partially provide artificial ventilation. Mechanical ventilation helps move a ...
to prevent airway compromise. Hypoxia (abnormally low oxygen levels) may require supplementary oxygen to balance blood oxygen levels, but if this is insufficient then again mechanical ventilation may be required to prevent complications caused by hypoxia. Treatment of the underlying cause is the next priority; pulmonary edema secondary to infection, for instance, would require the administration of appropriate antibiotic
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention ...
s or antivirals
Antiviral drugs are a class of medication used for treating viral infections. Most antivirals target specific viruses, while a broad-spectrum antiviral is effective against a wide range of viruses. Unlike most antibiotics, antiviral drugs do no ...
.
Cardiogenic pulmonary edema
Acute cardiogenic pulmonary edema often responds rapidly to medical treatment. Positioning upright may relieve symptoms. A loop diuretic
Loop diuretics are diuretics that act on the Na-K-Cl cotransporter along the thick ascending limb of the loop of Henle in the kidney. They are primarily used in medicine to treat hypertension and edema often due to congestive heart failure o ...
such as furosemide
Furosemide is a loop diuretic medication used to treat fluid build-up due to heart failure, liver scarring, or kidney disease. It may also be used for the treatment of high blood pressure. It can be taken by injection into a vein or by mo ...
(or Lasix®) is administered, often together with morphine
Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies ('' Papaver somniferum''). It is mainly used as a pain medication, and is also commonly used recreationally, or to make other illicit opioids. T ...
to reduce respiratory distress.[ Both diuretic and morphine may have ]vasodilator
Vasodilation is the widening of blood vessels. It results from relaxation of smooth muscle cells within the vessel walls, in particular in the large veins, large arteries, and smaller arterioles. The process is the opposite of vasoconstriction, ...
effects, but specific vasodilators may be used (particularly intravenous glyceryl trinitrate
Nitroglycerin (NG), (alternative spelling of nitroglycerine) also known as trinitroglycerin (TNG), nitro, glyceryl trinitrate (GTN), or 1,2,3-trinitroxypropane, is a dense, colorless, oily, explosive liquid most commonly produced by nitrating ...
or ISDN
Integrated Services Digital Network (ISDN) is a set of communication standards for simultaneous digital transmission of voice, video, data, and other network services over the digitalised circuits of the public switched telephone network. Wo ...
) provided the blood pressure is adequate.[
]Continuous positive airway pressure
Continuous positive airway pressure (CPAP) is a form of positive airway pressure (PAP) ventilation in which a constant level of pressure greater than atmospheric pressure is continuously applied to the upper respiratory tract of a person. The ap ...
and bilevel positive airway pressure
Positive airway pressure (PAP) is a mode of respiratory ventilation used in the treatment of sleep apnea. PAP ventilation is also commonly used for those who are critically ill in hospital with respiratory failure, in newborn infants (neonates), ...
(CPAP/BiPAP) has been demonstrated to reduce mortality and the need of mechanical ventilation in people with severe cardiogenic pulmonary edema.
It is possible for cardiogenic pulmonary edema to occur together with cardiogenic shock
Cardiogenic shock (CS) is a medical emergency resulting from inadequate blood flow due to the dysfunction of the ventricles of the heart.Textbooks of Internal MedicinHarrison's Principles of Internal Medicine 16th Edition, The McGraw-Hill Compan ...
, in which the cardiac output is insufficient to sustain an adequate blood pressure to the lungs. This can be treated with inotropic agents
An inotrope is an agent that alters the force or energy of muscular contractions. Negatively inotropic agents weaken the force of muscular contractions. Positively inotropic agents increase the strength of muscular contraction.
The term ''inotro ...
or by intra-aortic balloon pump
The intra-aortic balloon pump (IABP) is a mechanical device that increases myocardial oxygen perfusion and indirectly increases cardiac output through afterload reduction. It consists of a cylindrical polyurethane balloon that sits in the aorta, ...
, but this is regarded as temporary treatment while the underlying cause is addressed and the lungs recover.[
]
References
{{DEFAULTSORT:Pulmonary Edema
Medical emergencies
Respiratory diseases principally affecting the interstitium